Sacrificial catheter

ABSTRACT

A sacrificial catheter assembly and method of use for placing a functional catheter within the body of a patient, such as into the patient&#39;s vasculature, is disclosed. In one embodiment, the sacrificial catheter assembly comprises a sacrificial catheter including an elongate body that defines a longitudinally extending lumen. A stylet is removably received within the lumen of the sacrificial catheter such that the catheter and stylet can be advanced together to a target destination within the body of the patient. The sacrificial catheter is configured so as to then be proximally slid over the stylet to remove the sacrificial catheter from the body while the stylet remains in place at the target destination. A functional catheter can then be distally slid over the stylet to place the functional catheter at the target destination. The stylet can then be removed from the body of the patient.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 61/299,722, filed Jan. 29, 2010, and entitled“Sacrificial Catheter,” which is incorporated herein by reference in itsentirety.

BRIEF SUMMARY

Briefly summarized, embodiments of the present invention are directed toa sacrificial catheter assembly and method of use for placing afunctional catheter within the body of a patient, such as into thepatient's vasculature. In one embodiment, the sacrificial catheterassembly comprises a sacrificial catheter including an elongate bodythat defines a longitudinally extending lumen. A stylet is removablyreceived within the lumen of the sacrificial catheter such that thecatheter and stylet can be advanced together to a target destinationwithin the body of the patient. The sacrificial catheter is configuredso as to be proximally slid over the stylet to remove the sacrificialcatheter from the body while the stylet remains in place at the targetdestination. A functional catheter can then be distally slid over thestylet to place the functional catheter at the target destination. Thestylet can then be removed from the body of the patient.

As will be seen, the sacrificial catheter and stylet cooperate tofacilitate stylet-assisted placement of a functional catheter under arelatively broader range of catheter placement scenarios than wouldotherwise be possible. In addition, in one embodiment the stylet caninclude electrodes to enable the sacrificial catheter assembly tocooperate with an ECG monitoring system to advance the sacrificialcatheter and stylet to the target destination via ECG-based guidance.

These and other features of embodiments of the present invention willbecome more fully apparent from the following description and appendedclaims, or may be learned by the practice of embodiments of theinvention as set forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the present disclosure will be renderedby reference to specific embodiments thereof that are illustrated in theappended drawings. It is appreciated that these drawings depict onlytypical embodiments of the invention and are therefore not to beconsidered limiting of its scope. Example embodiments of the inventionwill be described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 is a simplified view of a patient and a catheter being insertedtherein as one example of an environment where an embodiment of thepresent invention can be practiced;

FIG. 2A is a side view of a sacrificial catheter in accordance with oneembodiment;

FIG. 2B is a side view of a stylet for use with the sacrificial catheterof FIG. 2A, in accordance with one embodiment;

FIG. 3 is a view of the sacrificial catheter of FIG. 2A with the styletof FIG. 2B disposed therein;

FIG. 4 is a side view of a sacrificial catheter including a plurality ofside holes in accordance with one embodiment;

FIG. 5 is a partial cross sectional side view of the catheter of FIG. 4with a stylet including band electrodes disposed therein in accordancewith one embodiment;

FIG. 6 is a partial cross sectional side view of the catheter of FIG. 4with a stylet including point electrodes disposed thereon in accordancewith one embodiment;

FIG. 7 shows end views of a sacrificial catheter and stylet includingone example of clocking features to facilitate mutual alignmenttherebetween;

FIG. 8 shows end views of a sacrificial catheter and stylet includinganother example of clocking features to facilitate mutual alignmenttherebetween; and

FIG. 9 is a cross sectional side view of a sacrificial catheterincluding conductive bands for sensing an ECG signal according to oneembodiment.

DETAILED DESCRIPTION OF SELECTED EMBODIMENTS

Reference will now be made to figures wherein like structures will beprovided with like reference designations. It is understood that thedrawings are diagrammatic and schematic representations of exemplaryembodiments of the present invention, and are neither limiting nornecessarily drawn to scale.

Embodiments of the present invention are generally directed to asacrificial catheter assembly and method of use for placing a functionalcatheter within the body of a patient, including the placement of acatheter into the patient's vasculature, for instance. In oneembodiment, the sacrificial catheter assembly includes a sacrificialcatheter with a preloaded stylet removably disposed within a lumenthereof. As will be seen, the sacrificial catheter and stylet cooperateto facilitate stylet-assisted placement of a functional catheter under arelatively broader range of catheter placement scenarios than wouldotherwise be possible.

For clarity it is to be understood that the word “proximal” refers to adirection relatively closer to a clinician using the device to bedescribed herein, while the word “distal” refers to a directionrelatively further from the clinician. For example, the end of acatheter placed within the body of a patient is considered a distal endof the catheter, while the catheter end remaining outside the body is aproximal end of the catheter. Further, the words “including,” “has,” and“having,” as used herein, including the claims, shall have the samemeaning as the word “comprising.”

Reference is first made to FIG. 1, which depicts one example environmentwherein the sacrificial catheter assembly described herein may beemployed. In particular, FIG. 1 depicts various details regarding theplacement of a functional catheter 72 within the vasculature of apatient 70 through a skin insertion site 73. The functional catheter 72generally includes a proximal portion 74 that remains exterior to thepatient and a distal potion 76 that resides within the patientvasculature after placement is complete. Specifically, FIG. 1 shows thata distal tip 76A of the functional catheter 72 is positioned at adesired position, or target destination, within the patient vasculature.In one embodiment, the target destination for the catheter distal tip76A is proximate the patient's heart, such as in the lower one-third(⅓^(rd)) portion of the Superior Vena Cava (“SVC”). Of course, thecatheter distal tip can be placed in a variety of other locations.

The functional catheter proximal portion 74 further includes abifurcation 74A that provides fluid communication between the one ormore lumens of the functional catheter 72 and one or more extension legs74B extending proximally from the bifurcation. As will be seen, thesacrificial catheter assembly to be described herein can be employed tofacilitate placement of the functional catheter 72 within the patientvasculature as depicted in FIG. 1, or in other intra-corporeal locationsas one skilled in the art will understand.

Reference is now made to FIGS. 2A and 2B, which depict elements of asacrificial catheter assembly, generally designated at 110 andconfigured in accordance with one example embodiment of the presentinvention. As shown, the sacrificial catheter assembly 110 includes anelongate sacrificial catheter 112 including a body defining an openproximal end 112A, an open distal end 112B, and a lumen 114 extendingtherebetween.

The sacrificial catheter 112 can define one of a variety of French sizesand cross sectional shapes while still benefiting from the principlesdescribed herein. The sacrificial catheter 112 can be formed from one ormore of a variety of materials, including polyurethane, polyvinylchloride, and/or silicone, for instance.

A handle 116 for assisting with handling of the sacrificial catheter isattached to the proximal end 112A of the sacrificial catheter 112 anddefines a passage therein that cooperates with the lumen 114 of thecatheter. A side port 117 or other suitable inlet is included with thehandle 116 to enable the catheter lumen 114 to be flushed when needed.In addition, the handle 116 includes a threaded connector 116A forlockably engaging a corresponding stylet lock ring, as will bedescribed. Note that the connector 116A can be configured in a varietyof other suitable ways to enable interconnection of the sacrificialcatheter with the stylet described further below.

The sacrificial catheter body 112 is configured for temporary insertioninto the vasculature or other suitable internal location of a patient bya clinician. In the present embodiment, a hydrophilic coating 118 isincluded on both the exterior surface of the sacrificial catheter 112and on the interior surface defining the lumen 114. The hydrophiliccoating 118 facilitates ease of removal of the sacrificial catheter 112from the patient body when its presence is no longer needed, as will bedescribed. In another embodiment, a hydrophilic coating can be appliedto an exterior surface of the stylet body 122 as well.

FIG. 2B shows that the sacrificial catheter assembly 110 furtherincludes a stylet 120 that is employed, together with the sacrificialcatheter 112, for assisting with the placement of a functional catheter,such as the catheter 72 shown in FIG. 1, in a desired target locationwithin the patient vasculature, as will be seen. In particular, thestylet 120 includes an elongate body 122 that defines a proximal end122A and a distal end 122B. In the present embodiment the stylet 120 isconfigured to be disposed within the lumen 114 of the sacrificialcatheter 112, as shown in FIG. 3, such that the distal end 122Bterminates proximate the distal end 112B of the sacrificial catheter112. In other embodiments, the length of the sacrificial catheter isless than that of the stylet such that a distal portion of the styletextends beyond the distal end of the sacrificial catheter when both arein place within the vasculature.

Note that, though the embodiments discussed herein describe use of astylet, in other embodiments a guidewire or other catheter guidingapparatus could be employed. As such, “stylet” is intended to includeother suitable, elongate guiding and/or stiffening apparatus, inaccordance with the principles of the embodiments described herein.

The stylet body 122 can be formed of stainless steel, a memory materialsuch as a nickel and titanium-containing alloy commonly known by theacronym “nitinol,” and/or other suitable materials. The stylet 120further includes a handle 126 that is attached at the proximal end 122Aof the stylet body 122 to assist with handling the stylet during use ofthe catheter assembly 110. Note that the handle 126 is sized so as toenable the sacrificial catheter 112 to slide over the stylet 120 andhandle when removal of the sacrificial catheter from the stylet isnecessary, as will be discussed further below. The stylet handle 126 canfurther include a separate lock ring 126A that releasably locks with theconnector 116A of the sacrificial catheter 112 so as to mate theproximal ends of the stylet 120 and catheter together. Note that thecatheter connector 116A and stylet lock ring 126 are but one example forreleasably mating the proximal ends of the sacrificial catheter 112 andstylet 120 and that many other configurations can be employed. Inanother embodiment, the sacrificial catheter handle 116, the stylethandle 126, or both can be omitted from the assembly.

The stylet body 122 further includes a plurality of depth markings 123to assist in placing a functional catheter using the sacrificialcatheter assembly, as will be described. The depth markings 123 caninclude alphanumeric identifiers, ticks, or other suitable indicia(including inch, cm, or mm gradations) to inform a clinician as to thedepth of insertion of the stylet 120 within the body of the patient.Similarly, and as seen in FIG. 2A, the sacrificial catheter 112 in oneembodiment can also include thereon depth markings 127 in inch, cm, mm,or other suitable gradations. The catheter depth markings 127 cancorrespond in longitudinal alignment with the depth markings 123 of thestylet 120 so as to assist with determining the depth of insertion ofthe functional catheter. In one embodiment, the depth markings 127 ofthe sacrificial catheter 112 can be correlated with the depth of one ormore sensors disposed on the stylet 120 or on the body of thesacrificial catheter 112 itself, as discussed further below.

In the present embodiment an ECG sensor, such as an electrode 124, isincluded with the stylet 120, as best seen in FIG. 2B. As shown, theelectrode 124 is positioned at the distal end 122B of the stylet body122 for use with an external ECG monitoring system to determineproximity of the stylet distal tip relative to an electricalimpulse-emitting node of the patient's heart, such as the SA node in oneexample. Such electrical impulses produced by the patient's heart arealso referred to herein as “ECG signals.” As will be seen, inclusion ofthe electrode 124 as an ECG sensor on the stylet enables the stylet tobe precisely guided, while disposed within the lumen 114 of thesacrificial catheter 112, through the patient vasculature to a desiredlocation proximate the patient's heart with the assistance of the ECGmonitoring system. One example of an ECG monitoring system can be foundin U.S. Patent Application Publication No. 2010/0036227, filed Sep. 10,2009, and entitled “Apparatus and Display Methods Relating toIntravascular Placement of a Catheter.” Another example of an ECGmonitoring system can be found in U.S. Patent Application PublicationNo. 2009/0259124, filed Apr. 21, 2009, and entitled “Method of Locatingthe Tip of a Central Venous Catheter.” Each of the foregoingapplications is incorporated herein by reference in its entirety. Notethat in other embodiments, no electrode need be included on the styletif ECG-assisted placement is not needed/desired. In yet anotherembodiment, the electrode(s) can be located on the sacrificial catheteritself.

A conductive pathway is established between the electrode 124 and theproximal end of the stylet handle/connector 126 to enable the transferof ECG signals detected by the electrode 124 along the length of thestylet 120. The conductive pathway in one embodiment is a conductivewire, ribbon, strand, etc. that is electrically connected to theelectrode 124 and extends to the handle/connector 126. In anotherembodiment, the conductive pathway can be the stylet body itself. Thehandle 126 of the stylet 120 is configured in the present embodiment asa connector to electrically connect with the external ECG monitoringsystem to enable ECG signals transferred from the electrode 124 via theconductive pathway to be received by the monitoring system. Forinstance, a tether from the ECG monitoring system can include analligator clip that removably attaches to the stylet handle 126 so as topermit the transfer of ECG signals from the stylet 120 to the ECGmonitoring system.

It should be noted that the stylet and electrode as depicted herein aremerely one example of a stylet/electrode configuration. Non-limitingexamples of other stylet configurations can be found in U.S. PatentApplication Publication No. 2010/0222664, filed Aug. 21, 2009, andentitled “Catheter Assembly Including ECG Sensor and MagneticAssemblies,” incorporated herein by reference in its entirety, and inthe patent application publications referenced further above.

FIGS. 4 and 5 depict details of another embodiment of the sacrificialcatheter assembly, wherein the distal portion of the sacrificialcatheter 112 defines a plurality of holes 130 through the catheter wallthat are each in communication with the lumen 114. So configured, thesacrificial catheter 112 can operably receive the stylet 120, as shownin FIG. 5. Note that the distal end of the sacrificial catheter 112 inthe present embodiment is tapered to provide for atraumatic insertioninto the patient vasculature.

In greater detail, FIG. 5 shows a cross sectional view of thesacrificial catheter 112 with the stylet 120 disposed therein. Thestylet body 122 in the present embodiment includes the distal electrode124 at the distal end 122B thereof, but also includes a plurality ofadditional electrodes 134 that are positioned in a spaced apartconfiguration along the length of the distal portion of the stylet body.

As with the distal electrode 124, each electrode 134 is configured todetect an ECG signal from the SA node or other ECG emitting portion ofthe patient heart when the sacrificial catheter 112 and preloaded stylet120 are disposed within the patient vasculature. As such, conductivepathways for each electrode 134 are included with the stylet 120 andextend to the stylet handle/connector 126, as before, to enable thestylet to operably connect with an external ECG monitoring system. Notethat the electrodes 134 can be spaced or grouped in one of a number ofways on the stylet body. Further note that in one embodiment the distalend electrode 124 can be omitted from the stylet 120, leaving only thespaced-apart electrodes 134. The number, size, type, and placement ofthe electrodes can vary according to need or application.

As best seen in FIG. 5, the holes 130 of the sacrificial catheter 112are arranged so as to longitudinally align with the additionalelectrodes 134 of the stylet body 122 when the stylet 120 is properlydisposed within the catheter lumen 114. The electrodes 134 in thepresent embodiment are configured as band electrodes, each extendingcircumferentially about the stylet body 122. In other embodiments, otherelectrode configurations can be employed. Note that non-limitingexamples of other multi-electrode stylet configurations can be found inU.S. Patent Application Publication No. 2010/0222664 (referenced above)and U.S. Patent Application No. 2011/0015533, filed Sep. 29, 2010, andentitled “Stylets for use with Apparatus for Intravascular Placement ofa Catheter,” each of which is incorporated herein by reference in itsentirety.

The sacrificial catheter assembly 110 is useful for placement of afunctional catheter, such as the catheter 72 shown in FIG. 1, insituations where prior advancement of a stylet or guidewire alone, orsimultaneous advancement of the stylet disposed within the functionalcatheter, is not possible. In such situations, the sacrificial catheter112 containing the stylet 120 preloaded therein can be employed.

The procedure below gives further details regarding functional catheterplacement using the sacrificial catheter assembly 110, according to oneembodiment. Though explained using the sacrificial catheter assemblyshown in FIGS. 4 and 5, the procedure can be applied to otherembodiments described and contemplated herein.

Before placement of the sacrificial catheter 112 into the patientvasculature using standard catheter introduction methods, the stylet 120is preloaded into the lumen 114 of the sacrificial catheter so as toassume the configuration shown in FIG. 5. If desired, the stylet 120 canbe mated to the sacrificial catheter 112 at the proximal ends thereof bythe separate stylet lock ring 126A, or by any other suitable manner. Thepreloaded sacrificial catheter 112 is then introduced into the patientvasculature and is advanced toward the patient's heart. As thesacrificial catheter 112 is advanced, each of the electrodes 124 and 134of the stylet 120 begins to detect the electrical impulses produced bythe SA node or other suitable node of the patient's heart, with the ECGsignal detected by each electrode varying as a function of distance fromthe SA node. Note that the sacrificial catheter lumen 114 can be flushedwith saline or other suitable liquid to ensure a conductive connectionbetween the blood in the vasculature and the electrodes within thecatheter lumen 114 via the catheter holes 130. Note further that, in oneembodiment, the electrodes 124 and 136 work in concert with a referenceand/or ground ECG electrode placed on the skin surface of the patient.In another embodiment, no such surface electrodes are used.

Monitoring via the ECG monitoring system of the ECG signals sensed byeach of the various electrodes 124 and 136 enables a clinician toobserve and analyze changes in the signal as the sacrificial catheter112 advances toward the SA node. When the received ECG signals match adesired profile, such as a maximized P-wave of the PQRS wave complex,the clinician can determine that the stylet distal end 122B has reacheda desired target position in the vasculature with respect to the SAnode. In one implementation, for example, this target position lieswithin the lower one-third (⅓^(rd)) portion of the superior vena cava(“SVC”). In this way, the electrode-equipped stylet 120 serves as anaide in confirming proper placement of the catheter distal end 112B.

Once the sacrificial catheter-covered stylet 120 has been placed asdesired within the vasculature, the sacrificial catheter 112 is nolonger needed and is slid proximally off the stylet 120 and removed fromthe body of the patient, all while keeping the stylet in place withinthe vasculature. In the present embodiment, the lock ring 126A is firstremoved from engagement with the stylet handle 126 and sacrificialcatheter handle 116 to separate the stylet 120 from the catheter 112.The hydrophilic coating 118 on the exterior and interior surfaces of thesacrificial catheter 112 facilitate ease of removal thereof withoutundesirably displacing the stylet 120 or producing intimal trauma to thepatient. It is thus seen that the sacrificial catheter is employed toassist with ultimate placement of a functional catheter, and is not usedfor therapeutic infusion or aspiration of fluids. The depth markings 123on the stylet body 122 are consulted at the insertion site or othersuitable location to determine how deeply the stylet has been insertedinto the vasculature and thus how far the functional catheter should beinserted.

The functional catheter 72 (FIG. 1) is then slid over the stylet 120 andinserted into the vasculature until its distal end is positionedproximate the distal end 122B of the stylet 120, which ensures properplacement of the functional catheter. The stylet 120 can then be removedfrom the patient while keeping the functional catheter 72 in place. Thefunctional catheter 72 can then be prepared as needed for use. Inaddition to use of the depth markings on the stylet body, othertechniques for determining the depth of functional catheter insertioninto the patient vasculature may also be used.

As shown in FIG. 6, in one possible embodiment, the stylet 120 includesone or more electrodes 134 that are point electrodes, instead of theband electrodes shown in FIG. 5. In this case, the handle of thesacrificial catheter, the handle of the stylet, or both can includefeatures to radially align the stylet with the sacrificial catheter suchthat the stylet electrodes 134 are not only longitudinally aligned withthe corresponding holes 130 of the sacrificial catheter 112, butradially aligned as well. FIG. 7 gives one example of clocking featuresthat can be included with the sacrificial catheter 112 and stylet 120,wherein the catheter handle 116 includes a hexagonally-shaped keyedsurface 140. The handle 126 of the stylet 120 includes a correspondinghexagonally-shaped keyed surface 144 that engages with the keyed surfaceof the catheter handle 116 when the stylet 120 mates with thesacrificial catheter 112. An indicator 148 can be included with thekeyed surfaces 140 and 144 to indicate a proper radial alignment betweenthe holes 130 and the electrodes 134, such as that shown in FIG. 6. FIG.8 gives another example of keyed surfaces 140 and 144, including acavity and correspondingly shaped protrusion on the catheter handle 116and stylet handle 126, respectively. In addition to these, many otherkeyed surface and clocking feature configurations for aligning thesacrificial catheter and stylet can be employed.

In another embodiment, the handles of the sacrificial catheter andstylet can be configured, such as interconnected with one another, so asto enable torqueing of the catheter assembly, which in turn enables theassembly to be steered during advancement within the patientvasculature. This interconnection can include suitable structure towithstand a longitudinal load thereon without separating or displacingthe handles with respect to one another. Such structure can include, forexample, a lock ring, collet, and/or compressed o-ring.

FIG. 9 depicts another embodiment of the sacrificial catheter 112,wherein the body thereof includes one or more electrically conductivebands 160 defined through the catheter wall thickness so as to pass ECGsignals therethrough. Such bands 160 can be operably linked withcorrespondingly placed electrodes on the stylet body 122 or in othersuitable ways so as to enable the detection of ECG signals when thesacrificial catheter 112 is disposed within the patient vasculature.Note that the number, shape, size, and usage of the conductive bands 160can vary from what is described herein.

Note that in one embodiment the stylet of the sacrificial catheterassembly can include one or more magnetic elements to enable thecatheter assembly to be used with a catheter placement system thatemploys magnetic-based stylet tip tracking in addition to ECG-based tipnavigation/position confirmation technology to accurately place thecatheter in the vasculature of the patient. The magnetic elements caninclude permanent magnets, electromagnets, or other magnetic apparatus.Further details regarding magnetic-based catheter tracking can be foundin U.S. Patent Application Publication No. 2010/0036227, referencedabove.

In one embodiment, the sacrificial catheter assembly can be employed inplacing multi-lumen catheters, such as that shown at 72 in FIG. 1,including catheters with staggered or split distal tips. Indeed, themulti-electrode stylet of the assembly can enable the distal tips ofsuch functional catheters to be placed in respective desired locationsonce the stylet has been placed and the sacrificial catheter removed.Further, it should be appreciated that in one embodiment the stylet canbe re-inserted into the functional catheter at any time subsequent toinitial placement to re-verify that the distal tip of the functionalcatheter is still positioned in a desired location within thevasculature. The depth markings on the stylet assist with such adetermination.

One skilled in the art will appreciate that the sacrificial catheterassembly can be employed in medical applications beyond what isexplicitly described herein, including coronary and arterialcatheterizations, for instance. Moreover, it is appreciated that insteadof ECG sensing electrodes, the stylet used with the sacrificial cathetercan employ other technologies, such as visual camera or Dopplertechnologies, for example.

In yet another embodiment, the distal end of the sacrificial cathetercan be configured to facilitate atraumatic insertion thereof. FIG. 6gives one example of this, wherein a distal segment 136 of thesacrificial catheter 112 includes a relatively soft durometer materialand is tapered to a relatively thin wall proximate the distal endthereof.

In one embodiment, it is appreciated that the sacrificial catheter canbe used to place a guidewire, conductive wire, stylet, or other elongatewire into the vasculature of the patient, after which the sacrificialcatheter is removed to leave the wire in place for use by a clinicianfor heart monitoring, etc. In this case, no additional component, suchas a functional catheter, is placed into the vasculature.

In another embodiment, the length of the catheter can vary from thelength of the stylet. For instance, the sacrificial catheter in oneembodiment can be shorter than the stylet. In one implementation, forexample, the catheter can be about 40 cm long while the stylet is about135 cm long. In such a case, the distal end of the stylet would bepositioned at the target destination, while the distal end of thesacrificial catheter would not, as the distal ends of the stylet andsacrificial catheter would not be co-terminal. Of course, a variety ofother possible sacrificial catheter and stylet length configurations canbe used.

Embodiments of the invention may be embodied in other specific formswithout departing from the spirit of the present disclosure. Thedescribed embodiments are to be considered in all respects only asillustrative, not restrictive. The scope of the embodiments is,therefore, indicated by the appended claims rather than by the foregoingdescription. All changes that come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

What is claimed is:
 1. A method for placing a medical device within avasculature of a patient using a sacrificial catheter including anelongate body defining a lumen and a stylet including a plurality ofelectrodes for sensing an ECG signal, the method comprising: advancingthe sacrificial catheter and the stylet disposed within the lumenthereof within the vasculature while monitoring an ECG signal sensed byat least one of the electrodes of the stylet; and removing thesacrificial catheter from the patient after a distal end of the styletis positioned at a desired target destination, the stylet remainingwithin the vasculature.
 2. The method for placing as defined in claim 1,further comprising: after removal of the sacrificial catheter, advancinga functional catheter over the stylet and through the vasculature untila distal end of the functional catheter is positioned at the targetdestination; and removing the stylet from the patient.
 3. The method forplacing as defined in claim 1, further comprising: determining thetarget destination by examination of ECG signals sensed by the pluralityof ECG electrodes.
 4. The method for placing as defined in claim 1,wherein the body defines a plurality of side holes in fluidcommunication with the lumen.
 5. The method for placing as defined inclaim 4, further comprising longitudinally aligning at least one of theelectrodes with a corresponding one of the side holes of the sacrificialcatheter when the stylet is received within the lumen.
 6. The method forplacing as defined in claim 4, further comprising radially aligning theelectrodes with the corresponding side holes of the sacrificialcatheter.
 7. The method for placing as defined in claim 6, furthercomprising flushing the lumen with a conductive liquid to ensure aconductive connection between blood in the vasculature and theelectrodes.
 8. The method for placing as defined in claim 4, furthercomprising correlating a plurality of depth markings on the sacrificialcatheter with a plurality of depth markings on the stylet.
 9. The methodfor placing as defined in claim 1, wherein monitoring an ECG signalfurther comprises monitoring electrical impulses produced by an SA nodeof the patient's heart, the ECG signal changing as a function of thedistance between the stylet and the SA node as the sacrificial catheteris advanced.
 10. The method for placing as defined in claim 1, whereinthe at least one of the electrodes works in concert with a referenceand/or ground ECG electrode placed on the skin surface of the patient.11. The method for placing as defined in claim 1, wherein advancing thesacrificial catheter further comprises determining when the distal endof the stylet is positioned at the desired target destination based onthe ECG signal.
 12. A method for placing a functional catheter within avasculature of a patient, the method comprising: advancing a sacrificialcatheter including a stylet disposed within a lumen thereof through thevasculature while monitoring an ECG signal sensed by at least one of aplurality of electrodes included with the stylet; removing thesacrificial catheter from the patient after a distal end of the styletis positioned at a target destination, the stylet remaining within thevasculature; and advancing a functional catheter over the stylet andthrough the vasculature until a distal end of the functional catheter ispositioned at the target destination.
 13. The method for placing asdefined in claim 12, further comprising: removing the stylet from thepatient after the functional catheter is positioned proximate the distalend of the stylet.
 14. The method for placing as defined in claim 12,further comprising: before advancing the functional catheter, observinga depth marker included on the stylet to determine the depth of thestylet within the vasculature.
 15. The method for placing as defined inclaim 12, further comprising: aligning a first clocking feature of thesacrificial catheter with a second clocking feature of the stylet toalign at least one of the electrodes with a hole defined through a wallof the sacrificial catheter.
 16. The method for placing as defined inclaim 15, further comprising flushing the lumen with a conductive liquidto ensure a conductive connection between blood in the vasculature andthe at least one of the electrodes aligned with the hole.
 17. The methodfor placing as defined in claim 12, wherein monitoring an ECG signalfurther comprises monitoring electrical impulses produced by an SA nodeof the patient's heart, the ECG signal changing as a function of thedistance between the stylet and the SA node as the sacrificial catheteris advanced.
 18. The method for placing as defined in claim 12, whereinthe at least one of the plurality of electrodes works in concert with areference and/or ground ECG electrode placed on the skin surface of thepatient.
 19. The method for placing as defined in claim 12, whereinadvancing a sacrificial catheter further comprises determining when thedistal end of the stylet is positioned at the target destination basedon the ECG signal.